This New Scanning Tool Shows How Genes in the Brain are ‘Switching Off’

Scientists have seen for the first time how genes in the human brain are "switching off" through a new scanning tool.

The on and off of genes in the brain is referred to as brain epigenetics, and so far, this gene activity in the human brain can only be detected in the dead. But now, researchers from the Harvard Medical School were able to see the DNA's on-and-off activity in a live human brain, and the technique is said to help detect early signs of Alzheimer's disease, schizophrenia and other disorders.

The new neuroimaging technique is a type of PET scan, which makes use of radioactive tracing chemicals that will allow scientists to see the brain at work. During the scan, the radioactive tracer is injected into the patient and binds to a type of enzyme called HDAC. According to New Scientist, the enzyme deactivates genes within the cells and stops them from producing the proteins they code for.

From the traditional brain scans, scientists could see where the tracer bounds to an enzyme, and thus see where in particular the enzyme is switching off genes.

The researchers conducted an experiment on the brains of eight healthy people and were surprised to find that the patterns of gene deactivation are similar among all participants. The research findings were published in the journal Science Translational Medicine.

"We think of it as a highly dynamic process, so we expected lots of variation between people," Jacob Hooker, associate professor of radiology at Harvard Medical School and lead author of the study, told New Scientist.

This led the researchers to conclude that there is a standard pattern for gene-expression levels, and that changes in the pattern could indicate an impending illness.

According to Stat News, Hooker and his team had already used the technique to see the gene-expression patterns in the brains of people with schizophrenia and Huntington's disease, and have recently secured funding to start doing tests on Alzheimer's patients.